Luminaire



y 1966 H. A. VAN DUSEN, JR 3,251,988

LUMINAIRE] Filed DeC. 5, 1963 LUMINAIRE Harold A. Van Dusen, Jr., South Milwaukee, Wis., as-

signor to McGraw-Edison Company, Milwaukee, Wis., a corporation of Delaware F iled Dec. 3, 1963, Ser. No. 327,846 Claims. (Cl. 240-128) This invention relates to luminaires and more particularly to new and improved structure for securing the reflector and refractor of an outdoor lighting fixture.

One type of prior art outdoor lighting fixture includes a head which is supported at its top or side and which in turn supports a downwardly extending lamp. Such luminaires also generally include a hood or reflector attached to the head and a light transmitting member or refractor supported by the reflector. To this end the refractor is provided with an annular flange at its upper end for cooperative engagement with a corresponding flange on the reflector. The reflector and refractor flanges are secured by a clamping 'band or ring which engages each of the flanges and which is provided with clamping uneans. Such clamping bands are generally fabricated from aluminum for purposes of conomy and lightness.

The refractors of this type of luminaire are sometimes composed of acrylic plastic, which has a substantially higher thermal expansion coefficient than that of the metallic reflector to which it is attached. As a result, the clamping bands must be spring loaded so that the plastic refractor can freely expand and contract without permanent deformation. These springs are generally composed of stainless steel and their opposite ends are attached to eyes integrally formed in the clamping band on the opposite side of an expansion gap provided therein. Because of the different metallic compositions of the clamping band and the loading spring, acidic moisture inherent in the atmosphere and which condenses on these components causes electroplating of the aluminum from the clamping band to the spring at their points of contact. Such electroplating causes deterioration of the clamping band so that after prolonged use it would fail at its weakest point of contact with the pressure spring, which is the integrally formed eyes.

It is an object of the invention to provide anchoring members for the spring of a reflector clamping band wherein the clamping band and the spring are of electro- United States Patent 0 M azstass Patented May 17, 1966 cry of the reflector 12. The flanges 14 and 16 are substantially co-extensive and are held in engagement by a generally V-in-cross-section clamping band or ring :18 which engages their lower and upper surfaces respectively.

A gap 20 is provided in clamping band 18 so that it may be affixed over the flanges 14 and 16 and also to permit expansion of the reflector 12 and the refractor 13. A spring 21 extends between an eye insert 212 disposed on one side of the gap 20 and a hook insert 23 disposed on the other side of the gap 20 to provide clamping-pressure to hold the band 18 securely against the flanges 14 and 16.

As seen more particularly in FIG. 3 the eye member 2-2 consists of a bent wire disposed within the clamping band 18 and having bight 26 formed intermediate its ends and extending through an aperture 27 in the'ring 18 to form an eye externally of the clamping band 18 for anchoring one end of the pressure spring 21. The opposite ends 29 of the wire 22 extend outwardly through small apertures 30 formed in the clamping band .18 and which are disposed on the opposite sides of the aperture 27. The ends 29 are also bent back against the outer surface of the clamping band 18 to serve as anchors to prevent movement of the wire 22.

The hook member 23 also consists of a wire disposed against the inner surface of the clamping band 18 and on the opposite side of the gap 20 relative to the eye member 22. One end 34 of the wire 23 extends outwardly of the clamping band 18 through a small aperture lytically dissimilar materials and the spring and the insert members are of electrolytically similar materials so that there will be no electrolytic action between the spring and its anchoring points on the band.

This and other objects and advantages of the instant invention will become more apparent from the detailed description thereof taken with the accompanying drawings wherein:

FIG. 1 is a side elevational view, with parts broken away of a luminaire incorporating the instant invention;

FIG. 2 is a top plan view of the luminaire shown in FIG. 1;

FIG. 3 is a view taken along lines 33 of FIG. 1; and

FIG. 4 is a view taken along lines 44 of FIG. 3.

Referring to the drawings in greater detail, FIG. l

3'5 and is bent backwardly away from the gap 20 to form a hook facing away from the eye -26 for anchoring the other end of the spring 21. The other end 36 of the wire 23 also extends through a small opening 37 in the clamping band 18 between the aperture 35 and the gap 20 in the band :18 and is bent downwardly against the outer surface of the clamping band 18 to form a second anchoring point for the wire 23.

The wires forming the members '22 and 23 are shown in FIG. 4 to be half round so that a relatively heavy wire can be employed while at the same time allowing the proper clearance between the .band 18 and the flanges '14 and 16. In addition, the rounded side of the wire nestles against the curved inner surface of the band 18.

The wires 22 and 23 and the spring 21 are preferably composed of electrolytically similar material such as stainless steel so that there will be no electrolytic action between these members which would result in the electroplating of one material on the other. While there will still be contact between the spring 21 and the electrolytically dissimilar material of the aluminum clamping band 18, the areas of such contact will be relatively large so that any deterioration of the clamping band 18 as a result of electroplating will be relatively insignificant compared to the total amount of material in contact. It can thus be seen that the eye insert member 22 and the hook insert member 23 provide rigid anchoring points for the spring 21 which will not deteriorate after prolonged use due to the electroplating of electrolytically dissimilar contacting metallic surfaces.

While only a single embodiment of the invention has been shown and described it is not intended to be limited thereby but only by the scope of the appended claims.

I claim:

1. In a luminaire, the combination of an inverted hollow hood portion having a lower opening, an optical member having an upper opening coextensive with the lower opening on said hood portion, a clamping band embraceably engaging the margins of each of said openings to support said optical member on said hood portion, an expansion gap provided in said clamping band, first and second anchoring means aflixed to said clamping hand on the opposite sides of said gap, each of said band and said spring means being of electrolytically dissimilar materials, said anchoring means and said spring,

means being of electrolytically similar materials.

2. In a luminaire, the combination of an inverted hollow hood portion having a lower end terminating in a circular rim, a light transmitting member having an upper circular rim coextensive with the rim on said hood por tion, an annular clamping ring embraceably engaging each of said rims to support said light transmitting member on said hood portion, an expansion gap provided in said clamping ring, first and second anchoring members aflixed to said clamping ring on the opposite sides of said gap, each of said anchoring members consisting of a bent wire disposed Within said clamping ring and having spring anchoring portions extendings outwardly through apertures formed in said ring, and spring means extending between said anchoring portions to hold said band in high pressure engagement against said rims, said clamping ring and said spring means being of electrolytically dissimilar materials, said spring means and said clamping members being of electrolytically similar materials.

3. In a luminaire, the combination of an inverted hollow hood portion having a lower end terminating in an outwardly extending flange, a refractor having an outwardly extending flange at its upper end for cooperatively engaging the flange on said hood portion, an annular generally V-in-cross-section clamping ring ,embraceably engaging each of said flanges to support said refractor on said hood portion, an expansion gap provided in said clamping ring, first and second anchoring members aflixed to said clamping ring on the opposite sides ofsaid gap, each of said anchoring members consisting of a bent wire disposed Within said clamping ring and having spring anchoring portions extending outwardly through apertures formed in said ring, and spring means extending between- 4 said anchoring portions to hold said ring in high presssure engagement against said flanges, said clamping ring and said spring means being of electrolytically dissimilar materials,-said spring means and said anchoring members being of electrolytically similar materials.

4. In a luminaire, the combination of an inverted hollow hood portion having a lower end terminating in a circular rim, a light transmitting member having an upper circular rim coextensive with the rim on said hood portion, an annular clamping ring embraceably engaging each of said rims to support said light transmitting member on said hood portion, an expansion gap provided in said clamping ring, first and second anchoring members aflixed to said clamping ring on the opposite sides of said gap,

each of said anchoring members consisting of a halfround bent wire disposed within said clamping ring and having each of its ends extending outwardly of said ring and bent downwardly toward the outer surface thereof to anchor said members in position, each of said members also having a spring anchoring portion extending outwardly through said ring, and spring means extending between said spring anchoring portions to hold said ring in high pressure engagement against said flanges, said. clamp ing ring and said spring means being of electrolytically dissimilar materials, said spring and said anchoring members being of electrolytically similar materials.

5. The combination set forth in claim 3 wherein the metallic composition of said clamping band includes aluminum and the metallic composition of said spring and said anchoring members includes a ferrous alloy.

References Cited by the Examiner UNITED STATES PATENTS 1,740,957 12/1929 Phillips 240-103 1,945,738 2/1934 Doans 240-103 2,309,279 1/1943 Smythe 287-86 2.731.280 1/1956 Goodliife et a1. 287-118 EVON C. BLUNK, Primary Examiner. 

1. IN A LUMINAIRE, THE COMBINATION OF AN INVERTED HOLLOW WOOD PORTION HAVNG A LOWER OPEING, AN OPTICAL MEMBER HAVING AN UPPER OPENING COEXTENSIVE WITH THE LOWER OPENING ON SAID HOOD PORTION, A CLAMPING BAND EMBRACEABLY ENGAGING THE MARGINS OF EACH OF SAID OPENINGS TO SUPPORT SAID OPTICAL MEMBER ON SAID HOOD PORTION, AN EXPANSION GAP PROVIDED IN SAID CLAMPING BAND, FIRST AND SECOND ANCHORING MEANS AFFIXED TO SAID CLAMPING BAND ON THE OPPOSITE SIDES OF SAID GAP, EACH OF SAID ANCHORING MEANS CONSISTING OF A MEMBER AFFIXED TO SAID CLAMPING BAND AND HAVING SPRING ANCHORING PORTIONS ON THE OUTER SURFACE THEREOF, AND SPRING MEANS EXTENDING BETWEEN SAID ANCHORING PORTIONS TO HOLD AID BAND IN HIGH PRESSURE ENGAGEMENT AGAINST SAID MARGINS, SAID CLAMPING BAND AND SAID SPRING MEANS BEING OF ELECTROYLTICALLY DISSIMILAR MATERIALS, SAID ANCHORING MEANS AND SAID SPRING MEANS BEING OF ELECTROLYTICALLY SIMILAR MATERIALS. 